In rivers and groundwater, in tap water and even in bottled mineral water: trifluoroacetic acid (TFA), the smallest of the PFAS molecules, also called “perennial pollutants”, threatens drinking quality of all water resources, according to a series of studies by the NGO network Pesticide Action Network Europe (PAN Europe) published between May and December 2024. Luxembourg, which contributed to the analysis through the Ecological movement is not spared.
PAN Europe first revealed in May 2024 “the largest known contamination of water on a European scale by a man-made chemical”. TFA, a degradation product of numerous substances, notably various phytosanitary, technical and refrigerant products (mainly from agriculture, but also from industries or combustion engines) is thus present “in all water samples” from ten EU countries.
Contaminated Alzette
23 surface water samples and six groundwater samples are thus contaminated, with concentrations ranging from 370 nanograms per liter (ng/L) to 3,300 ng/L, for an average of 1,180 ng/L. And if other PFAS are present in the samples, TFA alone represents more than 98% of the total PFAS detected, and at much higher concentration levels.
In Luxembourg, TFA is also present, both in surface water – its concentration in the Alzette exceeds 1,200 ng/l – and in groundwater, with more than 900 ng/L for all groundwater. of the country.
TFA present in drinking water
A finding that particularly concerns NGOs regarding the repercussions on the quality of drinking water. However, in July, a second study confirmed this concern: out of 55 samples of drinking water (tap water and mineral water) from 11 EU countries, 94% were contaminated, with an over-representation of TFA (more than 98 %) compared to other PFAS.
Tap water is particularly impacted: of the 36 samples analyzed, 34 are contaminated by TFA, for values ranging from less than 20 ng/L to 4,100 ng/L and for an average of 740 ng/L.
In addition, although bottled mineral water is supposed to be more preserved, it nevertheless presents traces of TFA in 12 of the 19 samples analyzed, with concentrations of up to 3,200 ng/L and an average load of 278 ng/L.
A Luxembourg mineral water with 430 ng/L of TFA
In December, PAN Europe detailed these latest results and revealed that the record goes to Villers natural mineral water, marketed in Belgium, and whose source is in Wallonia, with 3,400 ng/L. Vittel mineral water, in France, has a level of 400 ng/L.
The sample of mineral water from Luxembourg is also contaminated, with a TFA level of 430 ng/L. The name of the producer is however not revealed: at the request of the Ecological Movement, “the concerned Luxembourg brand has been anonymized”, specifies the report, “given the limited number of mineral water producers in Luxembourg” and then that the NGO considers that “disclosure of the brand name could excessively focus attention on this single manufacturer, instead of highlighting the overall problem”.
“It is worrying to note that it is now clearly established that bottled mineral water is also contaminated with the eternal chemical substance,” comments the Ecological Movement. “This is all the more problematic as consumers assume that it is a 'natural' and 'pure' product.”
Rare data to assess risks
But what is the real health risk of TFA contamination of water? Because it is this crucial question that is the subject of debate. However, data is rare to assess the health risks that this PFAS poses. “There are surprisingly few toxicological studies despite its widespread presence,” notes PAN Europe. And “based on current scientific knowledge of the toxicity of this chemical, the TFA levels we found still appear to be within safe limits,” acknowledges the network.
“However, the data on toxicity being limited and incomplete, an underestimate of the risk cannot be excluded,” he specifies. “The discourse that short-chain PFAS (like TFA) are harmless” is now “increasingly challenged by current scientific evidence,” he considers, citing two recent studies on chronic toxicity and toxicity. for the reproduction of TFA which “show effects similar to those of the better studied and better known PFAS (liver toxicity and birth defects)”.
Towards a legal limit on concentration rates?
However, there are currently no legal limits in the EU for TFA in surface water, groundwater or drinking water. PAN Europe therefore calls for the “immediate ban on PFAS-based pesticides” or the “setting of a safety limit for drinking water for TFA at EU level”.
The European Commission also took up the problem at the beginning of December by proposing to ban certain pesticides due to TFA pollution. And a standard limit value for “Total PFAS” of 500 ng/L in drinking water could come into force in the EU in 2026. Will TFA be included? “Discussions are still ongoing to determine how, and even if, this will be the case,” indicates PAN Europe.
The Luxembourg government, for its part, ensures that it “actively supports initiatives at the European level aimed at restricting the manufacture, marketing and use of PFAS including TFA” and “also advocates for harmonized limit values at the level European for the TFA”.
